Shelf



FIG. 1 is a front view of a shelf unit showing my new design.

FIG. 2 is a top view thereof;

FIG. 3 is a bottom view thereof;

FIG. 4 is a left side view thereof;

FIG. 5 is a right side view thereof;

FIG. 6 is a left-top front perspective view thereof; and,

FIG. 7; is a right-top front perspective view thereof.

Broken line disclosure is for illustrative purposes only and forms nopart of the claimed design.

Screws are shown in FIGS. 1, 2, 3, 4, 5, 7 and 8 for illustrativepurposes only and form no part of the claimed design.

I claim the ornamental design for a shelf, as shown and described.